A bourdon tube is a pressure sensing instrument designed for high-pressure systems such as oil pressure measuring. It consists of a ‘C’ shaped tube where the fluid enters through a damping choke. The other end of the tube is connected through a mechanical linkage and gears to a pointer. As fluid flows and pressure build-up, the tube will tend to unroll and move the mechanical linkage. The pressure ranges for a Bourdon tube can be vast as its movement is dependent on the metal from which it is made. For instance, a stiffer metal will be fitted for higher pressures. A bi-metal temperature compensator is also fitted at the end of the ‘C’ tube to correct for the temperature of flowing fluid, which will alter the tube’s stiffness and efficiency.